You can ask Nursery to offer him two naps, if that is what works best for you, and then give sleep limits on these naps. With time, he might be more ready to transition to one nap, and hopefully, that will be reflected in his nights sleep.
At home he will wake up around 7, nap around 10-11 and 3-4, then bed around 8. I think he has too much of a good time at nursery that he forgets to nap and only has an hour some point between 12-2. I’ve asked them to try and get him to nap twice but they’ve not been successful, same as when he’s with my mum 😬
What are the timings of his day in nursery and home? I think split nights are the hardest thing to deal with tbh ☠️